This invention pertains to quick connection devices and more particularly to a coupling assembly having a pre-installed portion for hermetically connecting two sealed low pressure systems.
In the manufacture and processing of elongate heat pipes or other low pressure systems charged with a working fluid, such as methanol, it has been considered difficult if not impossible to attach radial fittings or diagnostics prior to completing processing of such low pressure systems. During processing of such systems, movement of the product through a plant concurrent with manufacturing and processing operations necessarily tends to damage any such preattached device.
As a post-processing diagnostic of heat pipe performance, Bourdon tube compound gauges can indicate vacuum level during inoperative operating periods whereby they can be used to determine the integrity of heat pipe seals and joints. The Bourdon gauge also can detect pressures during operating periods by relying on the vapor pressure curve of methanol as a working fluid which can be related to operating temperature within plus or minus 2.degree. C. accuracy.
One problem, however, exists in attaching such a Bourdon tube compound gauge diagnostic to a fully processed heat pipe since at no time should the heat pipe hermetic seal or envelope be broken and exposed to ambient air since an inrush of non-condensable gases will occur so as to destroy the processed state of the heat pipe. Commercially available quick connections which are vacuum tight have tended to protrude radially to too great an extend from the side of the heat pipe surface; degrade with time, such as when employing rubber O-rings, seals or gaskets; and were costly.
Accordingly, there has been a need to apply radial fittings or diagnostics to heat pipes or the like without protruding too greatly radially of the pipe. It has further been desirable to attach a sealed portion of these connections to the heat pipe prior to the processing of the heat pipe, i.e. prior to preparing the heat pipe.